'Unsane': Claire Foy is losing her mind in first trailer for Steven Soderbergh's iPhone-shot thriller

Whether working in film or TV, Steven Soderbergh is an artist constantly looking to break new ground — as was just reconfirmed with his recent HBO series/branching-narrative app Mosaic. That splintered murder mystery was tailor-made to be experienced on your smartphone, where the story unfolded in the direction of the user’s own choosing. And for the director’s next effort, he’s once again turning to handheld devices — this time, to function as his camera.

Unsane is the upcoming psychological horror film starring Claire Foy (The Crown), and taking a cue from Sean Baker’s Tangerine, it was shot by Soderbergh using an iPhone. That formal gambit will no doubt make the upcoming film one of the spring’s most fascinating releases, and its first trailer only bolsters that notion. In the above clip, Foy’s protagonist finds herself menaced by a former boyfriend who won’t leave her alone. When she seeks help, however, she winds up getting herself committed to a psychiatric hospital (or has she committed herself?), where the lines between reality and fantasy become even more hopelessly blurred. What ensues, it appears, is the delusional madness of a bewildering sort, replete with hallucinations and murder — all of it aided by the participation of Joshua Leonard, Jay Pharoah, Juno Temple, Aimee Mullins, and Amy Irving.

Coming on the heels of The Knick, Logan Lucky, and Mosaic, Unsane appears to be yet another unconventional genre effort from the always masterful Soderbergh. The thriller debuts in theaters on March 23.